The present invention relates to a method for improving the flame retardance of a variety of aromatic organic polymers such as polyarylene ethers, polyetherimides, and polyesters by blending the respective polymers with poly(aryloxysiloxane)s. The resulting polymer blends also show an enhancement in properties such as an improved heat deflection temperature (HDT), solvent resistance, impact strength and ultimate elongation.
In copending application, Ser. No. 07/497,155, filed Mar. 21, 1990, and incorporated herein by reference, there is shown Polymeric Reaction Products of Biphenols and Organosilicon Materials, such as poly(aryloxysiloxane)s, and preferably poly(silyloxybiphenyleneoxide)s, hereinafter referred to as "PAS", consisting essentially of chemically combined groups of the formula, ##STR1## where R in formula (1) is selected from the same or different C.sub.(1-8) alkyl radicals, and R.sup.1 is selected from the same or different C.sub.(1-13) monovalent hydrocarbon radicals, and C.sub.1-13) monovalent hydrocarbon radicals substituted with monovalent radicals inert during condensation. PAS of formula (1) has been found to have improved hydrolytic stability. It also is a high molecular weight injection moldable material exhibiting flame resistant properties.
In copending application 07/646,902, now U.S. 5,187,243 filed Jan. 28, 1991, flame retardant transparent blends of aromatic polycarbonate and PAS are shown which exhibit excellent mechanical properties, such as Notched Izod Impact.